Electrical switches



Feb. 24, 1970 w. N, scH ET AL ECTRICAL SWITCHES 4 Sheets-Sheet 1 FiledApril 29, 1968 mm 0 MW mm m willz'amlc aad 9 1/ I. 4 I I M I ,0

Feb. 24, 1970 w, scH ET AL 3,497,644

ELECTRICAL SWITCHES 4 Sheets-Sheet 3 Filed April 29, 1968 27 Run/D9122;

EGZZ

Feb. 24, 1970 w. N. SCHINK ET AL 3,497,644

ELECTRICAL SWITCHES Filed April 29, 1968 4 Sheets-Sheet 4" United StatesPatent O F 3,497,644 ELECTRICAL SWITCHES William N. Schinlr, CrystalLake, and William J. Schaad, Winnetka, Ill., assignors to IndakManufacturing Corp., Northbroolr, Ill., a corporation of Illinois FiledApr. 29, 1968, Ser. No. 724,979 Int. 'Cl. Hlh 21/78, 27/08 US. Cl.200-11 Claims ABSTRACT OF THE DISCLOSURE This invention relates toelectrical switches generally, and pertains particularly to automotivetype switches, for use in automobiles, trucks, tractors and othervehicles.

Many practical applications for electrical switches, particularly inautomotive service, call for multi-position switches capable of carryingout various switching functions. Moreover, there is a wide variety ofrequirements for multiposition switches in various situations. Therequirements which switches are expected to meet are in a constant stateof change from year to year and from model to model. It is diflicult tomeet these requirements with existing switch constructions, particularlyin the face of the additional requirements of complete dependability,long service life, and low production cost.

One object of the present invention is to produce a basic switchconstruction which is adaptable to produce a line of many differentswitches, capable of fulfilling a wide variety of needs in variousapplications. The various switches produced in accordance with thepresent invention are similar in construction, so that many componentscan be used in common in various switches. Nevertheless, it is easy toproduce changes in the switch construction so that the various switchescan perform different switching functions to meet a variety of designrequirements. All of this is accomplished while maintainingdependability in their operation, long service life, and low productioncost.

The switch construction of the present invention involves a carriagewhich is rotatable to angularly spaced switching positions within acasing. The carriage is fitted with a contactor which is engageable witha plurality of stationary contact points. The casing is provided with aninsulating support for the contact points. Preferably, the insulatingsupport is also provided with insulating bosses or dummy contacts,interspersed between the contact points. The contactor preferablycomprises first and second diametrically opposite portions of differentangular widths. Thus, the angular width of the second portion ispreferably greater than that of the first portion, and also greater thanthe angular spacing between the various switching positions of thecontactor. The first portion of the contactor is of such narrow widththat it engages only one contact point or insulating boss in eachswitching position of the carriage. On the other hand, the secondportion of the contactor is of sufficient angular width to engage two ofthe contact points or insulating bosses at one or more switchingpositions of the carriage. With this basic construction, a wide varietyof switch designs may be produced by changing the arrangement of thecontact points and insulating bosses. The number of switch- 3,497,644Patented Feb. 24, 1970 ing positions can also be varied by changing thestops and the detents for the carriage. In each switching position, thecontactor generally engages three elements, which may be contact points,insulating bosses, or dummy contacts. By changing the arrangement of thecontact points, insulating bosses and dummy contacts, a wide variety ofswitching functions may be performed. It is easy to achieve smooth anddependable switching operations of the make before-break type. This isimportant in many switching operations in which it is highly desirableto avoid interrupting the circuit when switching operations are beingperformed. The wider portion of the contactor inherently has amake-before-break action. Moreover, the width of the narrower portion ofthe contactor can readily be adjusted to achieve a make-before-breakaction.

Whenever the circuit is broken between one of the contact points, thebreak occurs in the air, spaced away from the insulating support. Inthis way, any arcing occurs away from the board to avoid burning of theboard.

The contact points are preferably spaced around a circle on theinsulating support. The spacing between the contact points correspondsroughly to the spacing between the various switching positions of thecontactor. However, the spacing may be nonuniform in some instances. Inany particular switch design, insulating bosses or dummy contacts may beemployed in locations which are occupied by contact points in otherswitch designs. In this way, a wide variety of switches may be produced.

Further objects, advantages and features of the invention will appearfrom the following description, taken with the accompanying drawings, inwhich:

FIG. 1 is a front view of an electrical switch to be described as anillustrative embodiment of the present invention.

FIG. 2 is a side vie-w of the switch, showing the operating key inplace.

FIG. 3 is a rear view of the switch.

FIG. 4 is an elevational view showing the front or inner side of theterminal head of the switch, the view being taken generally as indicatedby the line 44 in FIG. 2.

FIG. 5 is a rear view of the swtich with the terminal head removed, theview being taken generally as indicated by the line 55 in FIG. 2.

FIG. 6 is a sectional view, taken generally along the line 6--6 in FIG.2.

FIG. 7 is a rear view of the rotary carriage for the switch.

FIG. 8 is a rear view of the casing, with the other components removed.

FIG. 9 is a diagrammatic rear view showing the Off position of thecontactor, the terminal head and contacts being shown in phantom.

FIG. 10 is a diagrammatic view similar to FIG. 9 but showing thecontactor in its second position, designated Run/Lights.

FIG. 11 is another diagrammatic view, similar to FIG. 9, but showing thecontactor in its third position, designated Run.

FIG. 12 is another diagrammatic view, similar to FIG. 9, but showing thecontactor in its fourth position, designated Start.

FIG. 13 is a longitudinal section, taken generally along the line 13-13in FIG. 9.

FIG. 14a is a fragmentary section, taken generally along the line 14a14ain FIG. 11.

FIG. 14b is a fragmentary section, taken generally along the line 14b14bin FIG. 12.

FIG. 15a is a fragmentary section, taken generally along the line 15a15a in FIG. 13 and showing the narrower end of the contactor.

FIGS. b, 15c and 15d are similar to FIG. 15a but show successivepositions of the contactor to illustrate the rocking movement thereof asthe contactor is moved between switching positions.

FIG. 15c is a fragmentary section, taken generally along the line 15e15ein FIG. 13, and showing the wider end of the contactor with thecontactor in the same position as in FIG. 15a.

FIGS. 151, 15g and 15h are similar to FIG. 15e but show successivepositions of the contactor, corresponding to the position shown in FIGS.15b, 15c and 15d.

FIG. 16 is a rear view of a modified switch, to be described as a secondembodiment of the invention.

FIGS. 17, 18, 19 and 20 are diagrammatic rear views of the contactor forthe second embodiment, the terminal head and contacts being shown inphantom. In these views, the contactor is shown in its four successiveswitching positions, designated Off, Run, Run/ Lights, and Start.

FIGS. 21 and 22 are side and rear views of another modified switch, tobe described as a third embodiment of the present invention.

FIGS. 23, 24 and 25 are diagrammatic rear views, showing the contactorof the third embodiment in those three successive switching positions,designated Off, Run and Start.

FIGS. 26 and 27 are rear and side views of another modified switch, tobe described as the fourth embodiment of the present invention.

FIGS. 28 and 29 are diagrammatic rear views, showing the contactor ofthe fourth embodiment in its two switching positions, designated Off andOn.

FIGS. 30 and 31 are rear and side views of still another modifiedswitch, to be described as a fifth embodiment.

FIGS. 32 and 33 are diagrammatic rear views, showing the contactor ofthe third embodiment in its two switching positions, designated Oif andOn.

The first embodiment, shown in FIGS. l-15, will now be described indetail. While the invention is applicable to switches of various types,the illustrated embodiment comprises a switch of the automotive type.The i1- lustrated switch 40 is particularly well adapted for use as akey type multi-position ignition switch for farm tractors or the like.Thus, the switch 40 has an operating key 42, shown in its position ofuse in FIG. 2.

It will be seen that the switch 40 comprises a housing or casing 44,made of metal or other suitable material. The casing 44 has a forwardlyprojecting axial bushing 46 which is preferably threaded for use inmounting the switch. The front end of the bushing 46 is formed with aslot 48 to receive the key 42.

As shown in FIG. 13, a carriage 50 is movably mounted within the casing44. The carriage 50 is preferably made of a plastic insulating material,.but other suitable materials may be employed. In this case, thecarriage 50 is of the rotary type. An axial shaft portion 52 projectsforwardly from the carriage 50 and is rotatable within the bushing 46,which provides a bearing for the shaft portion 52. A slot 54 is formedin the shaft portion 52 to receive the key 42 so that the key may beemployed to rotate the carriage 50.

A contactor 56 is mounted on the carriage 50 for rotary movementtherewith. In this case, the contactor 56 is generally in the form of ametal plate which is mounted on the rear side of the carriage 50,preferably in a plane perpendicular to the axis of the carriage 50. Thecontactor 56 is engageable with a series of stationary contacts, whichwill be described in detail presently. The contacts are supported bysuitable means, preferably in the form of a terminal head or board 58which is illustrated as forming a rear wall of the casing 44. Theterminal board 58 is preferably in the form of a plate made of aninsulating plastic material, or some other suitable material. Suitablemeans are provided to secure the terminal board 58 to the casing 44. Asshown, the

casing 44 is provided with a flange 60 which is spun or crimpedinwardly, behind the board 58.

The illustrated carriage 50 has a rearwardly projecting axial shaftportion 62 which is rotatably supported in an opening 64 formed in theterminal board 58. Thus, the terminal board 58 provides a rear bearingfor the carriage 50.

The carriage 50 preferably has an enlarged cylindrical guide portion 66,disposed just in front of the rear shaft portion 62. The guide portion66 extends through an axial opening 68, formed in the contactor 56.Thus, the guide portion 66 assists in locating the contactor 56 on thecarriage 50.

Other locating means are provided to cause the contactor 56 to rotatewith the carriage 50. As shown, the contactor 56 is formed with tabs orcars 70 which are bent forwardly from the contactor and are slidablyreceived in openings 72 formed in the carriage 50.

Means are provided to bias the contactor 56 rear wardly so that it willbe pressed into engagement with the various contacts on the terminalboard 58. As shown, the contactor 56 is biased rearwardly by a pair ofcompression coil springs 74, mounted in openings 76 which are formed inthe carriage 50.

One or more sealing rings 75 are preferably stretched around the frontshaft 52 to engage the inside of the bushing 46. A spring 77, affordingfrictional retention for the key 42, is also preferably mounted aroundthe shaft 52.

In the illustrated switch 40 the carriage 50 has a plurality ofswitching positions. Detent means are preferably provided to detain thecarriage in certain of these positions. Such detent means preferablycomprise detent balls 78, which in this case are located in the sameopenings 76 which also receive the springs 74. Insulating discs or othermembers 80 are preferably provided between the springs 74 and the balls78, to insulate the balls from the contactor 56.

The detent balls 78 on the carriage 50 are adapted to engage cooperatingdetent elements on the casing 44. As shown to best advantage in FIGS. 8and 13, such cooperating detent elements preferably take the form ofdepressions or recesses 81, 82, and 83, formed in the front wall 84 ofthe casing 44. The detent recesses 81 and 82 are circular in shape. Thisis also basically true of the detent recess '83, but ramps 86 arepreferably formed on one side of each recess 83, so as to enable thedetent balls 78 to ride easily out of the recess 83 when the carriage 50is rotated in one direction. The detent recesses 81, 82 and 83 areformed in pairs for engagement by the two detent balls 78.

The extent of movement of the carriage 50 is determined by a pair ofstops 88 and 90, formed on the carriage 50, and a cooperating stop 92,formed on the casing 44.

In this case, the carriage 50 is detented in its first three positions,designated Off, Run/Lights, and Run. A spring 94 is provided to returnthe carriage 50 from the fourth position designated Start, to the thirdposition, designated Run. The spring 94 is of the torsion type, having apair of prongs or arms 96, formed at its opposite ends. The arms 96 areinitially positioned by an arcuate stop 98 on the carriage 50. When thecarriage i rotated from the Run position to Start" position, one of thearms 96 engages a stop 98 on the casing, so that the movement of thecarriage is resiliently resisted by the spring 94.

The terminal board 58 is normally provided with a plurality of activecontacts, which are preferably in the form of rounded contact points,projecting from the front or inner side of the terminal board. Inaddition, the terminal board is preferably provided with one or moredummy contacts, which may be in the form of either insulating bosses,projecting forwardly from the board, or inactive contact points.

As shown to best advantage in FIG. 4, the illustrated contact board 58comprises two battery contact points 101 and 102, a magneto contactpoint 103, a contact point 104 for the lights, a Start contact point105, and a ground contact point 106. In addition, there are three dummycontacts comprising an insulating boss 107 between the contact points102 and 103, another insulating boss 108 between the points 104 and 105,and an inactive contact point 109 between the ground contact 106 and thebattery contact 101. The illustrated insulating bosses 107 and 108 arein the form of semi-perforations, punched, extruded or otherwise formedfrom the insulating board 84.

The illustrated contact points 101-106 are in the form of sphericallyrounded heads of rivets 111-116, extending through the insulating board58. The two battery rivets 111 and 112 are connected together by meansof a strap 114. Terminals 121, 123, 124, 125 and 126 are mounted on thecorresponding rivets 111, 113, 114, 115 and 116. The terminals arepreferably in the form of prongs, arranged to receive an appropriateconnector, whereby the switch is connected into the electrical circuitof the associated vehicle.

As previously mentioned, the illustrated contactor 56 is in the form ofa plate facing rearwardly on the carriage 50. It will seem that thecontactor 56 is formed with first and second contacting portions orsectors 131 and 132, on diametrically opposite sides of the axis of thecarriage 50. It is the contacting portions 131 and 132 which are adaptedto engage the contact points 101-106. The contactor 56 has a centralportion 133, whereby the con tacting portions 131 and 132 are connectedtogether.

The first contacting portion 131 of the contactor 56 is relativelynarrow in angular extent. In any particular switching position of thecontactor, the first contacting position 131 normally engages only onecontact point, or one dummy contact. However, in passing from onecontact point to another, the first contacting portion 131 normallyengages both contact points simultaneously on a momentary basis, toachieve a make-before-break action.

On the other hand, the second contacting portion 132 of the contactor 56is relatively wide in angular extent, so as to be adapted to form abridge between adjacent contact points. Thus, in any particular positionof the contactor 56, the contacting portion 132 normally engages twocontacts. In some cases this will be two active contact points, but inother cases the contacts will include one active contact point and adummy contact, or two dummy contacts.

With this construction, the switch may be designed to achieve a widevariety of switching functions. The active contact points and dummycontacts may be rearranged in many different ways, in accordance withthe switching functions to be carried out.

The particular switching functions of the first embodiment areillustrated to best advantage in FIGS. 9-12., which show the contactorin its four successive switching positions. In the position of FIG. 9designated Off, the first contacting portion 131 engages the magnetocontact point 103, while the second contacting portion 132 engages theground contact point 106 and the dummy contact point 109. In thisposition, the grounding of the magneto contact point 103 renders themagneto inoperative, so that the engine of the vehicle will not run.

In the position of FIG. 10 designated Run/Lights," the first contactingportion 131 engages the Lights contact point 104, while the secondcontacting portion 132 engages the battery contact point 101 and dummycontact point 109. Thus, the battery current is supplied to the lights.The magneto contact point 103 is no longer grounded, with the resultthat the magneto is rendered operative, so that the engine of thevehicle will run.

In the position of FIG. 11, designated Run, the first contacting portion131 engages the insulating boss 108, while the second contacting portion132 engages both of the battery contact points 101 and 102. In thisposition,

no circuit is established, but the magneto is in an operative conditionso that the engine will run.

In the position of FIG. 12, the first contacting portion 131 engages theStart contact point 105, while the second contacting segment 132 engagesthe battery contact 102 and the insulating boss 107. Thus, the startingmotor or other device is energized from the battery, so that thestarting motor will turn over the engine.

The dummy contacts 107109 are preferably interspersed with the activecontact points 101-106 in such a manner that the contactor 56 engagesthree contacts, either active or dummy, in all of the switchingpositions. The resulting tripod effect insures that firm contactpressure will be exerted between the contactor and each contact point.Moreover, the contactor is enabled to move smoothly between thesuccessive switching positions.

Preferably, the edges of the contacting portions 131 and 132 are bentaway from the contact board 58 so as to form ramps which assist in thesmooth movement of the contactor between the adjacent contacts. Thus, asshown in FIG. 14a, the contacting portion 131 is formed with ramps 141.As shown in FIG. 14b, the wider contacting portion 132 is formed withramps 142.

The provision of the contact points and the interspersed dummy contactsinsures that the contactor 56 will be spaced a substantial distance infront of the insulating board 58 in all positions of the contactor.Thus, the contactor never engages the surface of the insulating board,even when the contactor is moving away from one of the contact points,as the contactor is being moved between switching positions. In everyinstance the interruption of the circuit between any contact point andthe contactor takes place in the air, away from the insulating board, sothat any arcing produced by the interruption of the circuit will notburn the insulating board. This feature contributes to the long servicelife of the switch.

FIGS. l5a-l5h illustrate the manner in which the contactor 56 movesbetween the successive contact points with a rocking action, wherebythere is an effective wiping action between the contactor and thecontact points. The wiping action insures that good electrical contactwill always be established between the contactor and each contact point.Moreover, the wiping action keeps the contact points clean and spreadsthe wear on the contact points over a considerable area thereof.

The controlled rocking action between the contactor and the contactpoints is due to the arrangement whereby the narrower portion or sector1310f the contactor engages one contact point, while the wider sector132 engages a pair of contact points, at each switching position. Thusthe contact points are not diametrically opposite one another, but arearranged with a single contact point diametrically opposite from thespace between each pair of contact points. This arrangement results in aconstruction in which there are an odd number of positions for thecontact points around the circle defined by the centers of the contactpoints. Thus there are nine positions for the contact points in theswitch of FIGS. l15h. Some of these positions are occupied by contactpoints, while others are occupied by insulating bosses or other dummycontacts.

FIGS. 15a and 15.2 represent one of the switching positions of thecontactor 56. In this case, the narrower contacting sector 131 engagesthe contact point 103, while the wider contacting sector 132 engages thecontact points 106 and 109. FIGS. 15b, 15c and 15d representtransitional positions of the narrower contacting sector 131 as thecontactor is moved to the next switching position in which the narrowersector engages the contact point 104. In FIG. 15b it will be seen thatthe sector 131 has rocked in one direction into the valley between thecontact points 103 and 104. In FIG. 15c, the sector 131 has returned toan even keel, in which the sector engages both contact points 103 and104. In FIG. 15d, the sector 131 has rocked in the opposite direction asit moves away from the contact point 103 toward its next switchingposition, in which it is centered over the contact point 104.

FIGS. 151, 15g and 15h correspond to FIGS. 15b, 15c and 15d,respectively, and show the same rocking movement as it affects the widersegment 132. In FIG. 15 the sector 132 is rocking into the valleybetween the contact points 106 and 109. In FIG. 15g, the sector 132 hasreturned to an even keel and is centered over the contact point 109. InFIG. 1511, the sector 132 has rocked into the valley between the contactpoints 109 and 101. In the next switching position the sector 132 iscentered between the contact points 109 and 101 and is on an even keel,much the same as in FIG. 152.

In FIGS. 15b and 15 the contactor 56 is viewed from its opposite ends.This accounts for the opposite inclination of the contactor in the twoviews, which actually represent the same position of the contactor.Similarly, the oppositely inclined angles of the contactor in FIGS. 15dand 1511 are due to the fact that the contactor is being viewed fromopposite ends.

To provide for the tilting or rocking movement of the contactor 56, thedriving ears or lugs 70 are tapered, as shown in FIGS. 14a and 14b. Thusthe ears are able to rock in the openings 72.

The flexibility and versatility of the basic switch construction will beillustrated by describing several modified embodiments. The secondembodiment is shown in FIGS. 16-20 It comprises a modified ignitionswitch 200 having four switching positions, shown in FIGS. 17-20. Theswitch 200 may be the same in construction as the switch 40, except forthe fact that the contact points and dummy contacts are rearranged onthe insulating board 58. Thus, as shown, in FIGS. 17-20, the switch 200comprises two battery contact points 201 and 202, a magneto contactpoint 203, a contact point 204 for the lights, a start contact point205, and a ground contact point 206. There are three dummy contactscomprising an insulating boss 207 between the contact points 203 and204, an insulating boss 208 between the points 204 and 205, and aninsulating boss 209 between the points 206 and 201.

In the position of FIG. 17, designated Off, the first contacting portion131 of the contactor 56 engages the ground contact point 206. The widercontacting portion 132 engages the magneto contact 203 and theinsulating boss 207. Thus the magneto contact is grounded so that theengine of the vehicle will not run.

In the position of FIG. 18 designated Run, the first contacting portion131 engages the insulating boss 209. The second contacting portion 132engages the insulating boss 207 and the contact point 204. Thus nocircuit is established. The engine will run, because the magneto contactis not grounded.

In the position of FIG. 19, designated Run/Lights, the contactingportion 131 engages the battery contact 201. The wider contactingportion 132 engages the Lights contact 204 and the insulating boss 208.

In the fourth position of FIG. 20, the narrower contacting portion 131engages battery contact 202. The wider contacting portion 132 engagesthe Start contact 205 and the insulating boss 208.

The first and second embodiments 40 and 200 are in the form of fourposition switches. The third embodiment shown in FIGS. 21-25, is in theform of a threeposition switch 300. Here again, the switch 300 isbasically the same as the switch 40, except that the contact points anddummy contacts have been rearranged. Suitable changes are also made instops and detents, so as to accommodate the three operating positions.As shown in FIGS. 2325, the terminal board 58 of the modified switch 300is provided with first and second battery contact points 301 and 302,first and second Start contact points 303 and 304, and first and secondignition contact points 305 and 306. In addition, there are two dummycontacts comprising an insulating boss 307 disposed between the contactpoints 304 and 305, and an insulating boss 308 between the contactpoints 301 and 306, and somewhat closer to the contact point 301.

In the first switching position, shown in FIG. 23 and designated Off,the narrower contacting portion 131 of the contactor 56 engages theinsulating boss 307. The wider contacting portion 132 engages thebattery contact point 301 and the insulating boss 308. Thus no circuitis established.

In the position of FIG. 24, designated Run, the narrower contactingportion 131 engages the ignition contact point 305. The wider contactingportion 132 engages the battery contact points 301 and 302. Thus theignition circuit is energized from the battery.

In the-position of FIG. 25 designated Start, the narrower contactingportion 131 engages the second ignition contact point 306. The Widercontacting portion 132 engages the battery contact 302 and the Startcontact 303.

As before, the contactor 56 is spring returned from the Start positionof FIG. 25 to the Run position of FIG. 24. During the return movement ofthe contactor, the ignition'circuit is maintained without interruptionby virtue of the make-before-break action of the contactor 56. The widercontacting segment 132 is wide enough to engage both battery contactpoints 301 and 302 simultaneously, so that the circuit to the battery isinherently maintained. In the Start position of FIG. 25, the contactorengages only the second battery contact 302, while engaging both batterycontacts 301 and 302 in the Run position of FIG. 24.

The narrower contacting portion 131 is wide enough to engage both of.the ignition contacts 305 and 306 on a momentary basis during the returnmovement in which the contactor moves between the contacts 305 and 306.Thus there is no interruption of the ignition circuit.

FIGS. 26-29 illustrate a fourth embodiment in the form of a two-positionswitch 400. Here again, the switch is basically the same as before,except that the contacts are rearranged. Moreover, suitable changes aremade in the stops and detents to produce a two-position switch.

As shown in FIGS. 28 and 29, there are only two active contact points401 and 402, which are in adjacent positions on the terminal board 58.There are three dummy contacts, comprising insulating bosses 407, 408and 409.

In the switching position of FIG. 28, designated Off, the narrowercontacting portion 131 of the contactor 56 engages'the insulating boss407. The wider contacting segment 132 engages the contact point 401 andthe insulating boss 409. Thus no circuit is established.

In the switching position of FIG. 29, designated On, the narrowercontacting portion 131 engages the insulating boss 408. The widercontacting portion 132 engages the contact points 401 and 402.

FIGS. 30-33 illustrate still another embodiment in the form of anothertwo-position switch 500. As shown in FIGS. 32 and 33, the switch 500comprises contact points 501, 502, 503 and 504. The terminal board 58 isalso provided with dummy contacts in the form of insulating bosses 507and 508, adjacent the contact points 501 and 503. As before, the contactpoints 501-504 are preferably in the form of rounded heads of rivets511, 512, 513 and 514. The first terminal 521 is mounted on the rivets511 and 512, while the second terminal 522 is mounted on the rivets 513and 514. Thus the contact points 501 and 502 are connected together bythe terminal 521. Similarly, the contact points 503 and 504 areconnected together by the terminal 522.

In the switch 500 the contact points 501-504 are of large size toprovide high current carrying capacity. The terminals 521 and 522 arealso of large size.

In the switching position of FIG. 32, designated Off, the narrowercontacting portion or segment 131 engages the insulating boss 508. Thewider contact segment 132 engages the contact point 501 and theinsulating boss 507. Thus no circuit is established.

In the switching position of FIG. 33, designated On, the narrowercontacting segment 131 engages the contact point 503. The widercontacting segment 132 engages the contact points 501 and 502. Thus acircuit is established between the terminal 521, connected to the points501 and 502, and the terminal 522, connected to the point 503.

It will be evident that the switch construction of the present inventionis extremely versatile and may readily be adapted to produce a line orseries of switches capable of performing a wide variety of switchingfunctions. New switching functions can be achieved by rearranging theactive contact points and the dummy contacts on the terminal head. Thiscan readily be done, particularly in view of the fact that all of theactive contact points may be in the form of rivet heads. Thus thetooling cost involved in rearranging the contact points is quite low.

The same basic contactor construction can be employed for many differentswitches. Moreover, the casing and the carriage can be basically thesame for a Wide variety of switches. Only the detents and stops need bechanged to produce new switches. The tooling costs involved inrelocating the detents and the stops may be quite low. Normally, thecarriage is molded from an insulating plastic material. The stops may beproduced by using removable inserts in the mold. In this way, the stopscan readily be relocated.

The casing is normally die cast. The detent recess may be formed byusing movable inserts in the die or mold so that the detent recess mayreadily be relocated when new switches are to be produced.

In any particular switching position, the contactor may engage one, twoor three contact points. Thus the narrower contacting segment of thecontactor may engage one contact point. Alternatively, it may engage theinsulating boss or other dummy contact. The wider contacting segment mayengage two contact points in some instances. In other cases, the widercontacting segment may engage one contact point and an insulating boss,or two insulating bosses.

Several embodiments have been disclosed in detail, but it willberealized that many other new switches may be produced, using the basicswitch construction of the present invention. The switching functionsinvolved in a great many situations may be performed by the switches ofthe present invention.

Various other modifications, alternative constructions and equivalentsmay be employed without departing from the true spirit and scope of theinvention, as exemplified in the foregoing description and defined inthe following claims.

I claim:

1. An electrical switch, comprising a casing,

an insulating carriage rotatable in said casing to a plurality ofangularly spaced positions,

an insulating support mounted on said casing opposite said carriage,

a plurality of angularly spaced contact points mounted on saidinsulating support,

a contactor mounted on said carriage for movement therewith andengageable with said contact points, and spring means mounted on saidcarriage and biasing said contactor toward said contact points,

said contactor being in the form of a fiat conductive plate mounted onsaid carriage and substantially perpendicular to the axis of rotationthereof,

said contactor having first and second diametrically opposite portionsconstituting sectors of said conductive plate,

said first portion of said contactor being of such narrow angular extentas to be engageable with only one of said points at each position ofsaid carriage,

said second portion of said contactor being wider than said firstportion and of such angular width as to engage two of said points in atleast one position of said carriage,

said first and second portions of said contactor being symmetrical abouta common diametrical axis,

2. A switch according to claim 1,

in which the angular spacing between adjacent positions of said carriagecorresponds to one-ninth of a complete revolution,

said contact points being correspondingly spaced.

3. A switch according to claim 1,

including at least one dummy point projecting from said insulatingsupport toward said carriage for engagement by said contactor,

the spacing between said dummy point and the adjacent pointcorresponding to the spacing between the successive positions of saidcarriage.

4. An electrical switch, comprising a casing,

a carriage rotatable in said casing to a plurality of angularly spacedpositions,

a rotatable operating shaft extending forwardly from said carriage andout of said casing,

an insulating support mounted on said casing to the rear of saidcarriage,

a plurality of contact points mounted on said insulating support,

a contactor mounted on the rear side of said carriage for movementtherewith and engageable with said contact points,

and spring means biasing said contactor rearwardly relative to saidcarriage,

said carriage having an axially disposed cylindrical guide portionprojecting rearwardly therefrom,

said contactor having an axially disposed guide opening slidablyreceiving said cylindrical guide portion of said carriage,

said contactor having at least one locating tab projecting forwardlytherefrom,

said carriage being formed with a locating opening slidably receivingsaid locating tab to establish the operating position of said contactorrelative to said carriage.

5. A switch according to claim 4,

in which said contactor is formed with a plurality of such locatingtabs,

said carriage being formed with a plurality of locating openingsslidably receiving said tabs.

References Cited UNITED STATES PATENTS 2,715,661 8/1955 Miller 2004 XR3,239,615 3/1966 Schink et al. 200-44 3,334,198 8/1967 Bedocs et al.

ROBERT K. SCHAEFER, Primary Examiner J. R. SCOTT, Assistant Examiner US.Cl. X.R. 200-44

